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DM7446A, DM5447A/DM7447A
BCD to 7-Segment Decoders/Drivers
General Description
The 46A and 47A feature active-low outputs designed for
driving common-anode LEDs or incandescent indicators directly. All of the circuits have full ripple-blanking input/output controls and a lamp test input. Segment identification
and resultant displays are shown on a following page. Display patterns for BCD input counts above nine are unique
symbols to authenticate input conditions.
All of the circuits incorporate automatic leading and/or trailing-edge, zero-blanking control (RBI and RBO). Lamp test
(LT) of these devices may be performed at any time when
the BI/RBO node is at a high logic level. All types contain
June 1989
an overriding blanking input (BI) which can be used to control the lamp intensity (by pulsing) or to inhibit the outputs.
Features
Y
All circuit types feature lamp intensity modulation
capability
Y
Open-collector outputs drive indicators directly
Y
Lamp-test provision
Y
Leading/trailing zero suppression
DM7446A, DM5447A/DM7447A BCD to 7-Segment Decoders/Drivers
Connection Diagram
Dual-In-Line Package
TL/F/6518– 1
Order Number DM5447AJ, DM7446AN or DM7447AN
See NS Package Number J16A or N16E
C
1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.
TL/F/6518
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Absolute Maximum Ratings (Note)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage 7V
Input Voltage 5.5V
Operating Free Air Temperature Range
DM54
DM74 0
Storage Temperature Range
b
55§Ctoa125§C
Ctoa70§C
§
b
65§Ctoa150§C
Note:
The ‘‘Absolute Maximum Ratings’’ are those values
beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The
parametric values defined in the ‘‘Electrical Characteristics’’
table are not guaranteed at the absolute maximum ratings.
The ‘‘Recommended Operating Conditions’’ table will define
the conditions for actual device operation.
Recommended Operating Conditions
Symbol Parameter
V
CC
V
IH
V
IL
V
OH
I
OH
I
OL
I
OL
T
A
Supply Voltage 4.75 5 5.25 V
High Level Input Voltage 2 V
Low Level Input Voltage 0.8 V
High Level Output Voltage (a thru g) 30 V
High Level Output Current (BI/RBO)
Low Level Output Current (a thru g) 40 mA
Low Level Output Current (BI/RBO) 8 mA
Free Air Operating Temperature 0 70
Min Nom Max
’46A Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Symbol Parameter Conditions Min
e
V
I
V
OH
I
CEX
V
OL
I
I
I
IH
I
IL
I
OS
I
CC
Note 1: All typicals are at V
Note 2: I
Input Clamp Voltage V
High Level Output V
Voltage (BI/RBO) I
High Level Output V
Current (a thru g) V
Low Level Output V
Voltage V
Input Current@Max V
Input Voltage (Except BI/RBO)
High Level Input V
Current (Except BI/RBO)
Low Level Input V
Current V
Short Circuit V
Output Current
Supply Current V
is measured with all outputs open and all inputs at 4.5V.
CC
CC
CC
e
OH
CC
e
IL
CC
e
IH
CC
CC
CC
e
I
CC
CC
e
e
5V, T
CC
A
(Note 2)
25§C.
eb
e
Min, I
Min
12 mA
I
Max
e
Max, V
e
e
e
e
e
Max, V
Min, I
Min, V
Max, V
Max, V
30V
O
e
Min
IH
e
Max
OL
e
Max
IL
e
5.5V
I
e
2.4V
I
Max BI/RBO
0.4V
e
Max (BI/RBO)
e
Max
Others
DM7446A
Typ
(Note 1)
b
0.2 mA
b
Units
C
§
Max Units
1.5 V
2.4 3.7 V
250 mA
0.3 0.4 V
1mA
40 mA
b
4
b
1.6
b
4mA
60 103 mA
mA
2